Data for: Ant nests increase litter decomposition to mitigate the negative effect of warming in an alpine grassland ecosystem

Warming can decrease feeding activity of soil organisms and affect biogeochemical cycles in alpine ecosystems. Ants (Formica manchu) are active on their nest surface, and prefer a hot and dry environment. Therefore, warming may provide a favorable environment for their activity. We hypothesized that ants might benefit from warming and increase the robustness of ecosystem functions to warming. To test this hypothesis, we examined the effects of ant nests (ant nest absence vs. ant nest presence) and warming (ambient temperature, + 1.3°C and + 2.3°C) on litter decomposition, soil properties and the plant community in an alpine grassland ecosystem. Decomposition stations with two mesh sizes were used to differentiate effects of microorganisms (0.05mm) and macroinvertebrate (1cm) to litter decomposition. Ant nests increased litter decomposition with and without macroinvertebrates accessing the decomposition station when compared to plots without ant nests. Only the litter decomposition in ant nests with macroinvertebrates accessing the decomposition station was not negatively affected by warming. Plots with ant nests had greater soil organic carbon, nutrient contents and plant growth than plots without ant nests, regardless of warming. Consequently, ant nests can mitigate the negative effects of warming on litter decomposition and improve ecosystem functions under warming.

气候变暖可抑制土壤生物的取食活动，并干扰高山生态系统的生物地球化学循环。蚂蚁（Formica manchu）常在其蚁巢表面活动，偏好温热干燥的环境。因此，气候变暖或可为其活动营造适宜生境。据此，我们提出假说：蚂蚁或可从气候变暖中获益，并提升生态系统功能对变暖的抗干扰能力。为验证该假说，我们于高山草原生态系统中开展实验，探究蚁巢设置（有无蚁巢）与增温梯度（常温、增温1.3℃、增温2.3℃）对枯落物分解、土壤性质及植物群落的影响。实验采用两种孔径的分解样站，以分别解析微生物（microorganisms，0.05mm孔径）与大型无脊椎动物（macroinvertebrate，1cm孔径）对枯落物分解的作用。与无蚁巢样地相比，无论大型无脊椎动物能否进入分解样站，蚁巢均可提升枯落物分解速率。仅当大型无脊椎动物可进入分解样站时，蚁巢生境中的枯落物分解未受到变暖的负面影响。无论是否实施增温处理，有蚁巢的样地其土壤有机碳含量、养分水平与植物生长状况均显著优于无蚁巢样地。综上，蚁巢可缓解气候变暖对枯落物分解的负面影响，并改善增温条件下的生态系统功能。